The evolution in both commercial and residential indoor lighting has been characterized by progress in two directions simultaneously: along with improvements in technical/functional efficiency and variety of options in the illumination produced, there is ongoing development in the styling and aesthetic aspects of indoor light fixtures and enclosures; particularly there has been increasing interest in low-glare lighting fixtures that are architecturally integrated and appear to be built-in as part of the original building construction.
Indirect lighting, defined by Webster as “lighting reflected, as from a ceiling, or diffused so as to provide an even illumination without shadows” has become predominant in various forms that eliminate the annoyance of glare from a small bare bulb in the field of vision. For a light source of given power, i.e. wattage, the perceived glare is a function of the intensity of the visible light source, and thus the glare becomes reduced proportionately as the size of the visible area of the light source is increased through the use of reflected or translucent diffusion techniques.
The glass walls of fluorescent tubes are diffused or “frosted” to reduce glare, and while often deployed directly in industrial and utilitarian environments, they are more likely to be deployed with the well-known translucent diffusion panel for residential and office purposes, to reduce glare by increasing the visible area of the light source.
Even further glare reduction is obtained by the well known practice of concealing the light source behind a baffle of some kind and arranging for the light to be directed to and reflected from a white or light-colored surface such as a room ceiling. This technique is found in many contemporary homes with the baffles located high on one or more walls, e.g. in drapery valences.
In another low-glare approach, multiple small fixtures recessed in a ceiling can be arranged to provide uniform low glare illumination: glare is reduced by recessing the light source deeply enough to conceal the source from view at virtually any room location other than directly beneath, where it would be necessary to tilt ones head back far enough to look straight up into the fixture.
Beyond the functional goal of minimizing glare, a great deal of effort has gone into developing light fixture structures that harmonize function and appearance by blending in with the architecture.
There has been creative development and deployment of low-glare “wash” type indirect lighting fixtures: e.g. directed to floors for safety and security, directed to walls in a special manner to create some specially desired ambiance or mood effect such as relaxation in a living room or quiet dignity in a public building. Such fixtures can be recessed into a wall or ceiling and may include a specially shaped built-in reflector; the source lamps may be hidden by an offset location or by a close-fitting opaque light baffle located centrally in a symmetrical unit with a pair of reflectors.